The delivery of mail to multiple dwelling residences and other buildings requires a postal employee to use postal locks which are actuated by a key and are keyed alike so as to allow the postal employee access to all the postal locks on his or her route.
In the usual installation, the postal lock is located in a box behind a lid which faces the outside of the multiple dwelling residence or other building. Turning the key, slides the locking bolt of the postal lock to the retracted position and permits the lid to be opened, where a switch to open the door to a multiple dwelling residence or other building is located. In other instances, the box contains a key on a chain which is used to operate the lock which opens the building entrance door.
These various constructions give rise to vandalism and to the taking of keys and postal key locks from the box. A key could be made and a thief could then gain access to the various buildings on the postal worker's route.
The prior art solution to this problem was to have the key actuated postal lock on the inside of the building with the key slot accessible by an aperture through a steel plate from the outside of the building rather than through a lid which opened outwardly. The key would then be inserted from the outside through the aperture into the lock on the inside which was bolted to a plate inside. The movement of the bolt, actuated by the key, triggered a switch releasing the bolt to the building door lock. The inside postal lock was disposed in a housing with a panel door. Unfortunately, this left the postal key lock available to residents, employees, and others who gained entry to the building and who could then open the panel gaining access to the postal lock.
It is a specific object therefore of the invention to protect a postal lock against unauthorized access, while simultaneously allowing a postal employee access to multiple dwelling residences and other buildings to deliver mail. Furthermore, it is a broader object of the invention to provide such protection for other security systems operable via a lock/release element in a protective enclosure.